Cap and shell fastening for lamp-socket casings.



E. H. FREEMAN. GAP AND SHELL PASTENING POB. LAMP SOCKET .CASINGS.

APPLICATION FILED APILII. 1912.

1,090,527. rPanama 11.11.17, 1914.

EDGAR H. FREEMAN, oF TRENTON, NEW aEEsEY.

CAP AND SHELL EAsrENINe Eon LAMPfsoc'ifEm cAsrNesfy Application filedApril 11, 1912.V Serial No. 689,967.

Toall whom it may/ concerm Be it known that I, EDGAR H. FREEMAN,

. a4 citizen of theUnited States, residing at Trenton, in the county ofMercer and State of New Jersey, have invented certain new and usefulImprovements in Cap and Shell Fastenings for Lamp-Socket Casings, of

which the following is a specification.

This invention relates to the subject of metallic casings for electricallamp sockets, and more particularly to casings of the adjustable typewherein a plurality of locking positions are provided between the shelland cap parts of the casing so. as to enable the casing shell to notonly be readily and se' cui-ely united to the cap after the latter hasbeen fitted in place, but also to permit the shell to be so positionedwhen locked to the cap as to present the switch-key (of a key socket) ina readily accessible and convenient position for manipulation.

To this end the present invention contemplates apsimple and reliablefastening connection between the shell and capV parts of the lamp socketcasing, which admits of practically a universal circular adjustment forthe shellso ,that the same may be locked by the same locking means inany of a num-A ber of dierent positions, while at the same timepreserving all of the desirable features of that type of lamp socketcasing having what is termed in the trade a snap fastening."

A further object of the invention is to provide an improved fasteningconnection between the shell and the cap parts of a casing whichdispenses with the necessity of a locking hole or its equivalent tosecure the locked partsagainst rotation inieither direction, and againstseparation, thus greatly simplifying a fastening of this character whileat the Sametime retaining the maximum strength of the casing.

lith these and other objects in view, the invention consists iu certainnovel combinations and arrangements of the parts as will more fullyappear as the description proceeds, the novel features thereof beingpointed out in the appended claim.

For a full understanding of the invention, reference is to be had to thefollowing description and accompanying drawings, in which Figure 1 is aperspective view of a lamp socket casing constructedv in accordance withthe invention, the cap being shown as sepaforced intol the cap,

Aline 5-5 of Figfet.

Specification o f Letters Patent. B131", 17,1914." i

rated 'from andelevated above thei'body portion of the casing.v Fig.'2-is a -verticalfsecl tional viewthrough the lamp socket casing, the'body portion being shown asseparated from the brought into an therewith.Fig. 3-isf a siinilarview showing the position 'assumed bytheparts afterthe upper end of the body portion' has been before the body portion hasbeen rotated to bring the lugs of thecap into the lateral arms of thebayonet slots ot the body portion. Fig. 4 is a. similar view showingtheposition assumed by the parts after the body portion has been pushedinto the c ap and rotated to produce an interloekcap and properly`positioned with respect thereto to be forced into the cap-an'dinterlockingA 'connection ing connection between the members, and iFig. is atransverse-sectional view o-n the Corresponding and to in thefollowin description and indicated in all the views othe, drawings by:the same reference characters.` l

type of twopart casing. for'gelectrical lamp sockets, althoughforillustrzitive purposes the invention is showninkthc ndrawings l'It likepartsare referredl l A l V so The improved V fastening forming the sub-`i i,

embodi'e'd in a metallic lamp socket casing i comprising a metallicshell or body part l and a cap part: 2,5tl`1'e said'cap 'part 'beingprovided with a peripherallange 3 which telescopically' receives anendportion of the shell or body portion 1.

rIhre end of the shell l which is telescopically engaged by the flangedportion of cap 2 is formed with a series. of equidistant or regularlyspaced bayonet positioning slots 4 which open through the end of thoshell. The end of the shell may also be formed with a suitable slot oropening 5 to receive the switch key, although this slot the may beomitted Where the key is not used.

The flanged portion of the cap 2 is -formed with aseries of equidistantlugs G which correspond in number and position to the bayonetpositioning slots 4 of the shelll. Itwill thus be obvious that byinserting the end of the shell or body portion l into thecap 2 -in sucha manner that the lugs 6 will enter the bayonet slots 4, and thenrotating the shell or cap to bring the lugs into the lateral arms of thebayonet slots an interlocking 'connection will be produced which willhold the shell and ca`p together and prevent the l resilient lockingtongue 7 into an inopersaid members from being separated by adirectpull.

The mouth` of one of the bayonet positioning slots 4 is normallyclosedby means of a resilient looking tongue 7, the free end of.

the said locking tongue being substantially flush with the edge oi thecasing and being bent inwardly to provide a guide'lip 8 for engagementwith the end of that one of the lugs 6 which enters the bayonet slot.XVhen the shell is forced into the cap 2, the end of one of the lugs 6will ride downwardly upon the inwardly bent guide lip 8 and therebyforce the resilient locking'tongue 7 inwardly,

the parts assuming the position shown in` Fig. 3. Upon rotating eitherthe shell l or the cap 2 to bring the lugs 6 into the lateral arms ofthe bayonet slots, as indicated in Fig. 4, the resilient locking tongue7 u ill spring back into position so as to fit against one side of thelug and coperate therewith to prevent backward rotation of the, Shell.The mouth of the bayonet slot is then effectively closed by theresilient lockingtongue, so that the shell. andca can not beaccidentally detached from eac other.

The sresilient locking tongue 7 is shownas constituted by one end of astrip of spring` metal which is applied to the interior of the shell 1and has the lower or inner end thereof connected to the shell in anysuitable manner, such as by means of the rivet 9.- An intermediateportion of the spring strip is formed -with a plunger l0 -,which passesloosely through an opening in the side of the shell. When itis desiredto disconnect the shell andcap, it is merely necessary to press inwardlyupon the plunger 10 and throw the come! of this patent may be obtainedfor ve cents each, by addressing th Washington, D. C.

ative position, preparatory to manipulating the shell or cap to releasethe lugs 6 from the bayonet slots 4. v l

Attention may be directed to the fact that with the bayonet positioningslots 4 and the f lugs 6 arranged at uniform intervals, the

. casing may be interlocked with the cap with the key receiving slot 5on any side thereof, the neness of the adjustment which is possibledepending upon the number of bayonet slots and lugs which are employed.It will be obvious that any'desired number of the bayonet positioningslots may be utilized, although for ordinary purposes it has been found'that four of these positioning slots.; 'answer all practicalrequirements.

Having thus described the invention, what I claim as new and desire tosecure by Letters Patent, is y A cap .and shell fastening for lampsocket casings comprising, in combination, a cap member provided with aplurality of equidistant lugs, a shell member provided with a pluralityof equidistant bayonet slots corresponding in number and spacing to saidlugs, and a resilient locking tongue permanently fitted to one 4of saidmembers and having an exteriorly' exposed operating means, the saidlocking tongue being normally sprung into the mouth of one of thebayonet slots substantially flush with the edges thereof.

In testimony whereof-I hereunto affix my signature in the presence oftwo witnesses.

EDGAR H. FREEMAN.

Witnesses:

SARA M. RANDALL, ADA MARSH.

e Comminioner of Patents.

